Hello,
I'm looking for Normal Whole Brain Volume Dose Tolerance for single fraction SRS Brain plans. We have historically used V(1200cGy) < 10cc but with people using single isocenters to treat multiple mets it's becoming easier to treat more mets than before. I would assume we are able to push the "limit" of the historic normal whole brain tolerance but there isn't much literature with regards to this. If you do use a larger tolerance than above, please share and include literature references if there are any. Thank you.
Rich
Comments
Hello Rich, we still utilize V1200cGy<10cc conservative approach when possible*, and in fact, more conservatively, and we include the GTV volumes (most institutions don't). For 3 fraction treatments V18Gy for brain <30.2cc. For 5 fraction treatments V20<23cc. Agree that we should accumulate knowledge and push he limit based on evidence.
*With all this said, we often allow and exceed these limits when treating large number of targets and use the V1200cGy<10cc criteria for the largest contiguous V12. So, that means that V12 criteria is applied locally (no for global V12) and targets that have V12 connecting is considered as local.